Sanyo Electric Co., Ltd.

Ube Industries, Inc.

Yukihiro Oki

Masato Iwanaga

Atsushi Kaiduka

Koji Abe

Yoshiyuki Muraoka

Kazuhiro Miyoshi

Kentaro Takahashi

Akira Kinoshita

Nobumichi Nishida

Shuichi Yamashita

Masanori Ogi

Yoshihiko Ikeda

An object of the present disclosure is to provide a high-endurance and long-life nonaqueous electrolyte secondary battery including a battery case having sealing performance unlikely to be degraded. A nonaqueous electrolyte secondary battery according to an aspect of the present disclosure includes a closed-end cylindrical outer can, a sealing body that closes an opening of the outer can, a resin gasket disposed between the outer can and the sealing body, a sealing member interposed between the outer can and the gasket, and a nonaqueous electrolyte. The sealing member has a multilayer structure including a first sealing member layer, the main constituent of which is one selected from butadiene rubber, urethane rubber, silicone rubber, chloroprene rubber, and isoprene rubber, and a second sealing member layer, the main constituent of which is one selected from ethylene propylene rubber, ethylene propylene diene rubber, and fluoro rubber.

Nonaqueous electrolyte secondary battery

The nonaqueous electrolyte secondary battery includes a rolled electrode assemblyE formed by rolling a positive electrode plateand a negative electrode platewith a separatorinterposed therebetween, the separatoris fixed on the outermost periphery of the rolled electrode assemblyE with an adhesive tape for fixing a roll end, an exposed portion of a negative electrode substratewithout an active material mixture layeris placed on an outermost periphery side of the negative electrode plate, a negative electrode tabis connected to the negative electrode substrateon an outermost periphery side, and the adhesive tapeis not overlapped with a roll endof the positive electrode plateand a roll endof the negative electrode substrate. Thus the battery is seldom broken even when charging and discharging are repeatedly provided at high voltage.

Nonaqueous electrolyte secondary battery with rolled electrode assembly

A nonaqueous electrolyte secondary battery of the invention has a positive electrode having a positive electrode active material, a negative electrode, and a nonaqueous electrolyte having electrolyte salt in a nonaqueous solvent. The electric potential of the positive electrode active material is 4.4 to 4.6 V relative to lithium, and the nonaqueous electrolyte contains a compound expressed by structural formula (I) below. The quantity of compound added is preferably 0.1% to 2% by mass. Also, the positive electrode active material preferably comprises a mixture of a lithium-cobalt composite oxide which is LiCoOcontaining at least both zirconium and magnesium and a lithium-manganese-nickel composite oxide that has a layer structure and contains at least both manganese and nickel. Thanks to such structure, a nonaqueous electrolyte secondary battery can be provided that is charged to charging termination potential of 4.4 to 4.6 V relative to lithium and that has enhanced overcharging safety. [Chemical Formula 1] 

Nonaqueous electrolyte secondary battery, nonaqueous electrolyte, and charging method therefor

The preservation performance of a nonaqueous electrolyte secondary cell charged to high potential is improved while the initial capacity and the cycle property of the cell are also improved. The nonaqueous electrolyte secondary cell includes: a positive electrode having lithium phosphate and a positive electrode active material containing lithium cobalt compound oxide and lithium manganese nickel compound oxide having a layer structure, the lithium cobalt compound oxide having at least zirconium and magnesium added in LiCoO; a negative electrode having a negative electrode active material; and a nonaqueous electrolyte having a nonaqueous solvent and an electrolytic salt. The potential of the positive electrode is more than 4.3 V and 5.1 V or less based on lithium. The nonaqueous electrolyte contains vinylene carbonate as the nonaqueous solvent and, as the electrolytic salt, at least one of lithium bis(pentafluoroethane sulfonyl)imide and lithium bis(trifluoromethane sulfonyl)imide at 0.1 M or more and 0.5 M or less. The nonaqueous electrolyte contains 1,3-dioxane.

High-voltage charge type nonaqueous electrolyte secondary cell

A non-aqueous electrolyte secondary cell superior in resistance against continuous charging at high potential is provided. The non-aqueous electrolyte secondary cell includes: a positive electrode having lithium phosphate and a positive electrode active material comprising lithium cobalt oxide containing at least one selected from Mg, Al, Ti, and Zr; and a separator having pores having an average diameter of 0.05 to 0.2 &#x3bc;m.

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Tokushima, Japan

Yukihiro Oki